Allow trusted contributors to verify java-prettify changes

java-prettify and other public projects currently only allow project
owners to vote Verified+1. Allow others with Verified+1 permission
on gerrit to vote Verified+1 here, too, to smooth the contribution
process if they've done testing in a repository without zuul set up.

Change-Id: I0870e3f4dbf9fb4e16287470510469037f65a7ed